Alzheimer's disease (AD) is a severe neurodegenerative disease that leads to memory loss, mental illness and inevitable death. One of the modern hypotheses suggests that amyloid β-peptides, in particular, βA-(1-42), by binding to α7-acetylcholine receptor (AChR), form clusters in the form of amyloid plaques and lead to the destruction of brain tissue.
Elevated β-amyloid levels have also been reported in Down syndrome (DS) patients throughout their life, and are believed to cause AD in adults with DS.1 The results of a mouse study suggested intellectual disability in young DS patients might be treatable by Aβ-lowering drugs. 1 A transient cerebral ischemia can also significantly increase β-amyloid generation.2 
Deposition of Aβ-plaques has been reported to be a common pathological feature of HIV infection.3 It has been suggested that antiretroviral therapy (ART) may play a role in the elevated Aβ found in the brain of persons infected with HIV, and consequently these compounds may contribute to the cognitive decline observed in HIV associated neurocognitive disorders (HAND).3 
Traumatic brain injury (TBI) has also been reported to increase brain β-amyloid in humans and animals.4 Post-mortem studies of TBI victims have shown that approximately 30% have Aβ deposits.5 Evidence suggests these deposits are formed rapidly after injury; within 24 h of the initial impact.6 
Abnormal β-amyloid deposits in the thalamus have been reported after cerebral cortical infarction, and are suggested to be associated with secondary thalamic damage.7 
Deposition of β-amyloid, most commonly as diffuse plaques has also been reported in cases of chronic traumatic encephalopathy (CTE) following repetitive head injury, but has only been reported to occur in fewer than half the cases studied.8 
Today there exist several drugs that are used for the symptomatic treatment of AD. These drugs can, to some extent, delay the progression of the disease but not cure it. The most widely used class of drugs for the symptomatic treatment of AD therapy are compensatory cholinesterase inhibitors. However, the effectiveness of cholinesterase inhibitors is significantly reduced in the later stages of AD. Also, cholinesterase inhibitors are characterized by relatively high toxicity and a number of other side effects.9 There are also other medications for the symptomatic treatment of AD.10 
An important drawback of the compensatory therapy is that these drugs do not address the currently believed root cause of AD-β-amyloid accumulation. Therefore, intensive research is being conducted to find a way to address that root cause. It has been previously shown that an intermediate stage in the accumulation of βA in the cell is the formation of its complex with the type α7 AChRs.11 
Russian Federation patent no. 2372355 of Jun. 27, 2008 describes the peptide (NP-1) of the sequence:
[SEQ ID NO: 1]Glu-Trp-Asp-Leu-Val-Gly-Ile-Pro-Gly-Lys-Arg-Ser- Glu-Arg-Phe-Tyr-Glu-Cys-Cys-Lys-Gluwhich is the 173-193 fragment of the α7-subunit of the human acetylcholine receptor (AChR). Immunization by the above synthetic peptide produced antibodies capable of binding to the type α7 AChRs thereby preventing the formation of the complex sβA and, consequently, the formation of amyloid plaques. In behavioural tests, immunization with NP-1 prevented deterioration of spatial memory in animals with experimentally induced AD and prevented an increase in brain levels of βA. Also, immunization with NP-1 did not lead to deterioration of spatial memory in healthy animals.
The drawback of NP-1 (synthetic peptide 173-193) was that it was only active when administered in conjunction with complete Freund's adjuvant (a substance that stimulates the creation of antipeptide antibodies by the host's immune system), whose application in medical practice is not allowed. Therefore, a desirable feature when creating a pharmaceutical preparation for the immunotherapy of diseases, disorders or conditions characterized by or associated with β-amyloid accumulation such as Alzheimer's disease, is the creation of peptide structures that are immunogenic and have protective activity without the use of complete Freund's adjuvant.